Every once in a while the financial industry lives up to its critics’ worst expectations: that it operates against the interest of the investing public, in cahoots with captive regulators and Washington’s powerful elite.

This is exactly what happened Wednesday, when Securities and Exchange Commission Chairman Mary Schapiro had to cancel an Aug. 29 vote on sensible new rules to make money-market mutual funds safer. Although Schapiro had the support of Federal Reserve Chairman Ben S. Bernanke and leading conservative economists, she knew that three of the five commissioners would oppose her. This came after an intensive and often-misleading campaign by the $2.6 trillion money-fund industry to gloss over the inherent instability of the funds.

Among those swayed by the lobbying was Luis Aguilar, a Democratic commissioner (the other is Elisse Walter) who usually sides with Schapiro. Aguilar, a former general counsel of Invesco, one of the country’s major sponsors of money-market funds, met 11 times with industry lobbyists this year. Among his concerns was that additional rules might lead investors to funnel cash into shadowy, unregulated funds.